The present invention relates to a method of conveying reams of paper.
More specifically, the present invention relates to a method of conveying reams of paper along a path defined by at least a first and a second conveyor arranged in series in a given traveling direction and connected to each other at a transfer station; at least the first conveyor, upstream from the second in said traveling direction, being an endless conveyor comprising at least one pusher which is movable with the first conveyor, is of a given length, and engages and pushes a ream to said transfer station.
When a ream of paper is conveyed in known manner as described above, the pusher, which engages and feeds the ream from behind to the transfer station, releases the ream inside the transfer station, normally by a belt member driving the pusher about a pulley at the transfer station.
The above transfer method has several drawbacks, owing to the pusher, as it moves about the pulley, not only imparting variable acceleration to the ream being transferred, which is thus extremely difficult to transfer to the second conveyor in a precise position, but also exerting on the ream localized pressure along a line as opposed to on a surface. This latter drawback is normally negligible when transferring solid bodies, but is critical when transferring reams. That is, if the ream being transferred is even only slightly deformed, the line of contact between the pusher and the ream may be reduced to only a few points, thus resulting in partial damage to, and subsequent rejection of, the ream.
It is an object of the present invention to provide a method of conveying reams of paper, which is straightforward and cheap to implement and, at the same time, provides for eliminating the aforementioned drawbacks.
According to the present invention, there is provided a method of conveying reams of paper along a path defined by at least a first and a second conveyor arranged in series in a given traveling direction and connected to each other at a transfer station; at least the first conveyor, upstream from the second in said traveling direction, being an endless conveyor comprising at least one pusher which is movable with the first conveyor, is of a given length, and engages and pushes a ream to said transfer station; the method being characterized by comprising the steps of feeding the ream to said transfer station at a first speed by means of said first conveyor; and transferring the ream to the second conveyor by bringing the ream to a second speed greater than said first speed, so as to detach the ream from the pusher by a distance at least equal to said length before the ream leaves said first conveyor.
The method defined above preferably also comprises the further step of conveying the ream, by means of said second conveyor, at a third speed lower than said second speed.
By exploiting the difference between the second and third speed, it is therefore possible to release the ream in a specific position on the second conveyor.
The present invention also relates to a device for conveying reams of paper.
According to the present invention, there is provided a device for conveying reams of paper along a given path, the device comprising at least a first and a second conveyor arranged in series in a given traveling direction and connected to each other at a transfer station; at least said first conveyor, upstream from the second in said traveling direction, being an endless conveyor comprising at least one pusher which is of a given length and movable with the first conveyor to engage and push a respective ream to said transfer station; the device being characterized by comprising first drive means connected to said first conveyor to feed the ream to said transfer station at a first speed; and accelerating means for engaging the ream at said transfer station and conveying the ream at a second speed greater than said first speed and such as, in use, to detach the ream from the pusher by a distance at least equal to said length before the ream leaves said first conveyor.